The destruction by nematodes (especially by so-called root-knot nematodes), acarids and insects presents a serious problem to agriculture. A wide variety of field crops are in need of protection from nematodes, acarids and/or insects including such valuable crops as soybeans, corn, peanuts, cotton, alfalfa and tobacco. In addition, vegetables, such as tomatoes, potatoes, sugarbeet, carrots and the like as well as fruits, nuts, ornamentals and seed bed crops such as apples, peaches, peas, citrus fruit and grapes may also require protection from the ravages of such pests.
One particularly difficult type of insect to control are those which, at one or more stages of their life, inhabit the soil and cause destruction to the roots of agriculturally valuable plants. Representative of this type of insect is the corn rootworm.
Corn rootworms are the larvae of several species of beetles of the genus Diabrotica. These larvae cause severe damage to the roots of corn plants, particularly in fields where one corn crop follows another in successive seasons. The adult beetles lay their eggs in the soil of a maturing corn crop The eggs lay dormant in the soil until the following spring. Then they hatch in response to favorable soil temperatures and the larvae feed on the roots of young corn plants causing reduction in yield and/or the stalks to topple over when subjected to either wind or wet soil conditions. The fallen stalks cannot be satisfactorily harvested by mechanical harvesters causing significant losses.
Control of such soil-dwelling insects and nematodes is difficult in that most organophosphorous-type insecticidal and nematicidal compounds have an undesirably short residual life in soil. Accordingly, it is completely unexpected that the novel organophosphorous-substituted tetrazolinone compounds of this invention exhibit desirable foliar insecticidal and acaricidal properties coupled with admirable control of soil-dwelling insects and nematodes.
U.S. Pat. No. 3,780,053 to Miesel shows a class of 5-oxo(thioxo)-l,3-(alkyl, alkenyl or cycloalkyl)-1,2,4-triazolin-4-yl methyl phosphorous derivatives having insecticidal, acaricidal and antihelminthic activity.
Japanese Patent No 1982-14929 to Matsui et al shows certain phosphorothiomethyl-substituted triazolinones which exhibit insecticidal and acaricidal activity.
U.S. Pat. No. 3,973,010 to Dawes et al shows a class of triazolyl phosphoric esters having insecticidal and acaricidal activity.
U.S. Pat. No. 4,211,703 to Berges shows certain phosphoroalkyl and esterified phosphoroalkyl substituted tetrazole thioazoles useful as intermediates in the preparation of certain antibiotics.
European Patent 65,216 to Kubel et al shows certain 5-(1,2,4-triazol-5-ylmethyl)(di)thiophosphonate derivatives having insecticidal, acaricidal, nematicidal and fungicidal activity.
German Offenlegungsschrift 25 27 676 shows a class of 5-triazolylmethyl thiophosph(on)ates useful as insecticides, acaricides and nematicides.
British Patent 932,388 to Sherlock shows certain heterocyclic thiophosphoric acid esters exhibiting acaricidal activity.
Tsuge et al, J. Org. Chem. 45, 5130 (1980); Horwitz et al, J. Am. Chem. Soc. 81, 3076 (1959); and Vandensavel et al, J. Org Chem , 88, 675 (1973) all show processes for the production of tetrazolinones.
However, while certain of the above-listed publications disclose pesticidally active compounds, it would nevertheless be desirable to possess compounds which exhibited enhanced control of pests, particularly of soil-dwelling insects.
Accordingly, it is an object of this invention to provide novel compounds, exhibiting unexpectedly desirable pesticidal activity.
It is a further object of this invention to provide novel compounds exhibiting admirable activity against soil dwelling insects.
It is another object of this invention to provide pesticidal compositions comprising such novel compounds.
It is yet another object of this invention to provide methods of controlling pests employing such compositions.
The above objects, and the additional objects, will become more fully apparent from the following disclosure and accompanying Examples.